1. Field of the Invention
The present invention relates to an electronic timepiece for driving to rotate a time hand based on rotation of a motor.
2. Description of the Prior Art
Conventionally, there has been used an electronic timepiece for indicating time by driving to rotate a time hand of an hour hand or the like by a motor. The motor is driven by a battery and therefore, power consumption by the motor is preferably as less as possible.
Conventionally, an electronic timepiece using a primary battery is designed to use a battery having a capacity satisfying prescribed service life based on current for operating the electronic timepiece and therefore, there is not provided a power saving function for reducing power consumption.
Meanwhile, as in an electronic timepiece described in Japanese Patent Laid-Open No. 304555/1997 or Japanese Patent Laid-Open No. 319143/1998, according to a power generating timepiece using a secondary battery chargeable by a power generating element of a solar cell or the like, when there is detected a state of being incapable of generating power such as a state of not receiving light, a motor for driving a hand is made to stop driving to rotate, that is, operation of the hand is made to stop. Thereby, when the power generating element cannot generate power, a reduction in power consumption can be achieved.
Meanwhile, generally, a user rarely uses a timepiece in a way of confirming time by taking a look at the timepiece around the clock.
For example, there is a time band of not taking a look at a timepiece as in the case of sleeping or the like. Further, according to an electronic wrist watch, there is a time band of not taking a look at the timepiece by taking off the timepiece from the wrist as in the case of sleeping or taking a bath. Further, there also is a way of using a timepiece in which the timepiece is ordinarily kept in a drawer and is used as needed and in that case, the timepiece may be kept in the drawer for days without taking a look at the timepiece.
Even in such a case of not taking a look at a timepiece, since a hand is operated in the timepiece, there poses a problem that power is wastefully consumed.
It is a problem of the invention to reduce power consumption by operating a hand of a timepiece only when needed.
According to the invention, there is provided an electronic timepiece characterized in comprising a motor for driving to rotate a time hand, time setting means for setting hand operation stop time and hand operation start time of the time hand, storing means for storing the hand operation stop time and the hand operation start time set by the hand operation time setting means, first counting means for counting a drive amount necessary for driving the time hand to a regular position by counting an elapse time period since the motor has been stopped, second counting means for counting a drive amount of fast feeding the motor, time detecting means for detecting arrival of time set to the storing means, and controlling means for controlling rotation of the motor, wherein the controlling means stops the rotation of the motor when the time detecting means detects arrival of the hand operation stop time and restarts time indication by fast feeding the motor at a predetermined speed or more until the drive amount counted by the first counting means and the drive amount counted by the second counting means coincide with each other when the time detecting means detects arrival of the hand operation start time after stopping the motor and driving the motor at the predetermined speed.
When the time detecting means detects arrival of the hand operation stop time, the controlling means stops rotation of the motor and when the time detecting means detects arrival of the hand operation start time after stopping the motor, the controlling means restarts time indication by fast feeding the motor at the predetermined speed or more until the drive amount counted by the first counting means and the drive amount counted by the second counting means coincide with each other and thereafter driving the motor at the predetermined speed.
Here, there may be constructed a constitution further comprising hand operation stopping means for forcibly stopping to operate the time hand and hand operation stop detecting means for detecting operation of the hand operation stopping means, wherein the controlling means stops the rotation of the motor when the hand operation stop detecting means detects the operation of the hand operation stopping means.
Further, there may be constructed a constitution further comprising hand operation starting means for forcibly starting to operate the time hand and hand operation start detecting means for detecting operation of the hand operation starting means, wherein the controlling means restarts the time indication by fast feeding the motor at the predetermined speed or more until the drive amount counted by the first counting means and the drive amount counted by the second counting means coincide with each other when the hand operation start detecting means detects the operation of the hand operation starting means after stopping the motor and thereafter driving the motor at the predetermined speed.
Further, there may be constructed a constitution further comprising alarming means for setting alarm time to the storing means and generating alarm when the alarm time arrives at the time setting means, wherein the controlling means restarts the time indication by fast feeding the motor at the predetermined speed or more until the drive amount counted by the first counting means and the drive amount counted by the second counting means coincide with each other when the time detecting means detects a predetermined time period before the alarm time after stopping the motor and thereafter driving the motor at the predetermined speed.
Further, there may be construction a constitution in which the timepiece is constituted by an hour hand, a minute hand and a second hand and the motor is constituted by a first motor for driving the second hand and a second motor for driving the hour hand and the minute hand.
Further, there may be constructed a constitution further comprising mode switching means for switching a hand operation stop time setting mode for setting the hand operation stop time and a hand operation start time setting mode for setting the hand operation start time and hand operation time setting means for setting the hand operation stop time by the hand operation stop time setting mode and setting the hand operation start time by the hand operation start time setting mode at the time setting means, wherein the controlling means controls the first motor to move the second hand selectively to indicating positions of the hand operation stop time setting mode and the hand operation start time setting mode in response to mode switching by the mode switching means.
Further, there may be constructed a constitution in which the mode switching means switches the mode further to an alarm time setting mode for setting alarm time and the hand operation time setting means sets the alarm time by the alarm time setting mode, wherein the controlling means moves the second hand selectively to indicating positions of the hand operation stop time setting mode, the hand operation start time setting mode and the alarm time setting mode in response to the mode switching by the mode switching means.
Further, there may be constructed a constitution further comprising crown operation detecting means for detecting operation of a crown at the mode switching means for carrying out the mode switching in accordance with the operation of the crown detected by the crown operation detecting means.